From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756146Ab1GJUbC (ORCPT ); Sun, 10 Jul 2011 16:31:02 -0400 Received: from mail-yw0-f46.google.com ([209.85.213.46]:48667 "EHLO mail-yw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754888Ab1GJUa7 convert rfc822-to-8bit (ORCPT ); Sun, 10 Jul 2011 16:30:59 -0400 MIME-Version: 1.0 In-Reply-To: <20110710173530.GA16954@linux.vnet.ibm.com> References: <201107072047.14429.kernelmail.jms@gmail.com> <20110707195845.GD6014@linux.vnet.ibm.com> <201107072147.12751.kernelmail.jms@gmail.com> <20110708002903.GI6014@linux.vnet.ibm.com> <20110709100900.GB6014@linux.vnet.ibm.com> <20110710032510.GG6014@linux.vnet.ibm.com> <20110710171626.GK6014@linux.vnet.ibm.com> <20110710173530.GA16954@linux.vnet.ibm.com> Date: Sun, 10 Jul 2011 21:30:58 +0100 Message-ID: Subject: Re: PROBLEM: 3.0-rc kernels unbootable since -rc3 From: julie Sullivan To: paulmck@linux.vnet.ibm.com Cc: linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > But maybe not that much thought.  My current guess is that your > configuration is somehow causing some RCU callbacks to be executed > during early boot, and that these callbacks are attempting to use kernel > features that are not yet initialized.  If my guess is correct, then > the reason that enabling RCU_BOOST makes things work is that it prevents > RCU callbacks from executing until after the scheduler is up and running. > > So I added another commit to the jms.2011.07.07a branch in the -rcu > git tree.  If my guesses are correct, this will allow your system to > boot, possibly emitting a warning on the way up.  When you get a chance > to try this out, please let me know how it goes. > >                                                        Thanx, Paul Fantastic, now we boot perfectly! I also tried the same treatment on v3.0-rc5 and -rc6 (i.e. revert f8b7fc6b514f34a51875 and a46e0899eec7a3069bcad then add those 8 commits from the jms.2011.07.07a branch) with the same success. Thanks for giving me back 3.0-rc4, -rc5 and -rc6! Cheers Julie